Metadata Understanding

Posted by Ken Ashworth
Jan 24, 2007 at 11:36 AM

Graham Rhind wrote:
>...then any outliner contains
>metadata, because a note name is metadata, a keyword is metadata, a title is metadata.
>Even the words within the text could be regarded as metadata because they can be
>searched.
>

Yes, all of these programs overlay a database, or in it’s simpilist terms (abstract) a two-dimensional table - where each row is a record (node or item), and each column is a Field with the intersecting cell containing the FieldData. Starting with a new database, or empty table, you populate the table by adding nodes.

Since each node is a record, everything that describes (defines) the node is an attribute (FieldName:FieldData or column).

All programs reveal a basic set of node attributes - Node Title and display characteristics (font apperance), node detail (user entered data). Some reveal, and make available, a set of system fields - default fields required for each node.

For example: the inclusion of a time/date stamp in the node detail is usage of a system field, or changing the icon of a node in the tree pane. The availability (to the user) of these system fields varies among programs.

For example: Treepad allows for the placement of such system fields as CurrentNodeTile, ParentNodeTitle, Sibling… within the item detail (RTF editor).

Taking this to the next level are those programs that allow for user-defined attributes (FieldName:FieldData or column).

Continuing with the example of UR, starting from a new database select a node, then Tools|Attributes, then click on the column heading Category to sort the list. Now you can scroll thru the list and see those fields that are considered System Fields (checked) and those that are User-Defined (not checked).

From Tools|Attributes window you can select and Insert an existing field and it will be revealed in the Item Attributes pane (View|Other Windows|Item Attributes), or you can create a new (user-defined) field, then select and Insert.

Through the Tools|Attributes window and the Items Attributes pane, UR reveals (and makes available, data entry) the coulmns of our two-dimensional table.

Since each record (row or node) contains all columns, all columns are available for each node. It just depends on which column (field) you want to reveal in the Item Attributes pane.

Those programs that allow for the creation of user-defined fields add a level of structure to the freeform nature of these programs. In the case of UR you can add further structure thru the use of Templates.

Later,
KenA